add GetById endpoint

Tsi1.Api/Tsi1.Api/Controllers/UserController.cs

@@ -102,5 +102,20 @@ namespace Tsi1.Api.Controllers
 
             return Ok(result.Data);
         }
+
+        [Authorize(Roles = UserTypes.Student + ", " + UserTypes.Professor)]
+        [HttpGet("GetById/{userId}")]
+        public async Task<IActionResult> GetById(int userId)
+        {
+            var result = await _userService.GetById(userId);
+
+            if (result.HasError)
+            {
+                return BadRequest(result.Message);
+            }
+
+            return Ok(result.Data);
+        }
+
     }
 }

Tsi1.Api/Tsi1.BusinessLayer/Dtos/ProfessorPreviewDto.cs

+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Tsi1.BusinessLayer.Dtos
+{
+    public class ProfessorPreviewDto
+    {
+        public string IdentityCard { get; set; }
+    }
+}

Tsi1.Api/Tsi1.BusinessLayer/Dtos/StudentPreviewDto.cs

+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Tsi1.BusinessLayer.Dtos
+{
+    public class StudentPreviewDto
+    {
+        public string IdentityCard { get; set; }
+
+        public int Age { get; set; }
+    }
+}

Tsi1.Api/Tsi1.BusinessLayer/Dtos/UserPreviewDto.cs

@@ -13,5 +13,9 @@ namespace Tsi1.BusinessLayer.Dtos
         public string FirstName { get; set; }
 
         public string LastName { get; set; }
+
+        public StudentPreviewDto Student { get; set; }
+
+        public ProfessorPreviewDto Professor { get; set; }
     }
 }

Tsi1.Api/Tsi1.BusinessLayer/Helpers/MappingProfile.cs

@@ -22,6 +22,8 @@ namespace Tsi1.BusinessLayer.Helpers
             CreateMap<Message, MessageCreateDto>();
             CreateMap<User, UserPreviewDto>();
             CreateMap<User, UserRegisterDto>();
+            CreateMap<Student, StudentPreviewDto>();
+            CreateMap<Professor, ProfessorPreviewDto>();
             CreateMap<Course, CourseCreateDto>();
             CreateMap<Course, CoursePreviewDto>();
 
@@ -36,8 +38,10 @@ namespace Tsi1.BusinessLayer.Helpers
             CreateMap<MessageCreateDto, Message>();
             CreateMap<UserPreviewDto, User>();
             CreateMap<UserRegisterDto, User>();
+            CreateMap<StudentPreviewDto, Student>();
+            CreateMap<ProfessorPreviewDto, Professor>();
             CreateMap<CourseCreateDto, Course>();
-            CreateMap<CoursePreviewDto, Course>();
+            CreateMap<CoursePreviewDto, Course>();        
         }
     }
 }

Tsi1.Api/Tsi1.BusinessLayer/Interfaces/IUserService.cs

@@ -15,5 +15,7 @@ namespace Tsi1.BusinessLayer.Interfaces
         Task<ServiceResult<User>> Create(UserRegisterDto dto, string type);
 
         Task<ServiceResult<List<UserPreviewDto>>> GetAll(int tenantId);
+
+        Task<ServiceResult<UserPreviewDto>> GetById(int userId);
     }
 }

Tsi1.Api/Tsi1.BusinessLayer/Services/UserService.cs

 using AutoMapper;
 using Microsoft.EntityFrameworkCore;
+using Org.BouncyCastle.Math.EC.Rfc7748;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -98,5 +99,44 @@ namespace Tsi1.BusinessLayer.Services
 
             return result;
         }
+
+        public async Task<ServiceResult<UserPreviewDto>> GetById(int userId)
+        {
+            var result = new ServiceResult<UserPreviewDto>();
+
+            var user = await _context.Users
+                .Include(x => x.UserType)
+                .Include(x => x.Student)
+                .Include(x => x.Professor)
+                .FirstOrDefaultAsync(x => x.Id == userId);
+
+            if (user == null)
+            {
+                result.HasError = true;
+                result.Message = string.Format(ErrorMessages.UserDoesNotExist, userId);
+                return result;
+            }
+
+            var userType = user.UserType.Name;
+
+            if (userType == UserTypes.Student && user.Student == null)
+            {
+                result.HasError = true;
+                result.Message = string.Format(ErrorMessages.StudentDoesNotExist, userId);
+                return result;                
+            }
+            else if(userType == UserTypes.Professor && user.Professor == null)
+            {
+                result.HasError = true;
+                result.Message = string.Format(ErrorMessages.ProffesorDoesNotExist, userId);
+                return result;
+            }
+
+            var userDto = _mapper.Map<UserPreviewDto>(user);
+
+            result.Data = userDto;
+
+            return result;
+        }
     }
 }